tomcat6.0启动不了，求助高手！！！

[2012-03-18 17:50:54] [info] Procrun (2.0.4.0) started
[2012-03-18 17:50:54] [info] Running Service...
[2012-03-18 17:50:56] [info] Starting service...
[2012-03-18 17:50:57] [info] Error occurred during initialization of VM
[2012-03-18 17:50:57] [info] java/lang/NoClassDefFoundError
[2012-03-18 17:50:57] [info] : java/lang/Object
[2012-03-18 18:16:55] [info] Procrun (2.0.4.0) started
[2012-03-18 18:16:55] [info] Running Service...
[2012-03-18 18:16:55] [info] Starting service...
[2012-03-18 18:16:55] [info] Error occurred during initialization of VM
[2012-03-18 18:16:55] [info] java/lang/NoClassDefFoundError
[2012-03-18 18:16:55] [info] : java/lang/Object

日志文件显示：Error occurred during initialization of VM（在初始化虚拟机时发生错误），有没有人遇到过呀，该怎么解决啊求助